The social dimension of patient decision-making is relatively understudied, although oncologists routinely recommend that patients bring a spouse or close friend to a medical visit. As African American patients talk about their options with thei loved ones, we need to understand how these social relationships effect patient attitudes and beliefs about chronicity, mortality, care, and cure to shape the decisions patients make, including whether to participate in clinical trials. The goal of this study is to develop an inter-personal framework to clarify how social relationships influence the way African American patients make decisions about lung cancer care. Lung cancer is the leading cause of cancer death in the US; overall mortality rates are estimated at 72% for men and 41% for women. Outcomes are worse for African American patients who are generally diagnosed at younger ages, with more advanced disease, and greater comorbidities. Non-small cell lung cancer, in particular, is often diagnosed at advanced stages resulting in poor prognosis. Differences in how the disease itself manifests produce several treatment options even in the context of low overall survival rates. As African American patients weigh such treatment options with their significant others, we need to understand how these conversations affect patient attitudes and beliefs to shape patient decisions, including whether to participate in clinical trials. Though several different behavioral constructs explore dimensions of social support and social influence, they fall short of adequately describing the actual dynamic between patients and their significant others when they talk about making decisions outside of the doctor's office. This study will evaluate the applicability of these different constructs to inter-personal decision-making, and then use anthropological methods to explore the patient-family dynamic to elucidate an inter-personal decision-making framework in lung cancer care. Specific study objectives are to: 1) Develop a preliminary framework of inter-personal decision-making that incorporates applicable behavioral constructs (e.g. perceived versus enacted social support, social influence, dyadic coping,) to delineate the moment-to-moment interactions between patient and significant other; 2) Survey African American lung cancer patients d 18 months of diagnosis (n=100) using the framework constructs; 3) Refine the framework using qualitative data from joint interviews with a subsample of 20 patients and their spouses over three time points (post-diagnosis, treatment, after-care; n= 60 interviews) conducted at home or in community. This research is significant because it combines behavioral theory with patient-reported experiential data to investigate an important dimension of medical decision-making. Findings will lead to evidence-based psycho- social interventions to reduce treatment outcome disparities in African American lung cancer. PUBLIC HEALTH RELEVANCE: The relevance of this research to public health lies in increasing our understanding of how African American patients use conversations with their spouse or significant other to think about the decisions they need to make in the course of lung cancer treatment. We can use this understanding to better inform physician practice in caring for lung cancer patients and thereby address treatment and outcome disparities in this minority population. This work will lead to new interventions that will provide additional psychosocial resources for African American patients, their families and their physicians to help them make the decisions that are most appropriate to their particular circumstances.